In Defense of Malthus

Thomas Robert Malthus is arguably the most maligned economist in history. For over two hundred years, since the first publication of his book An Essay on the Principle of Population, Malthus' work has been misunderstood and misrepresented, and severe, alarming predictions have been attached to his name. Malthus got some important things wrong, but these flaws will be the subject of an upcoming column. This column will address what other people, both detractors and supporters, got wrong when writing about him.

Before delving into what Malthus wrote and how critics misconstrued his views, it is helpful to give an idea of the controversy that surround Malthus' Essay. The first edition, published in 1798, was a fairly short volume that laid out Malthus' essential points, discussed below. It inspired an onslaught of criticism and denunciation of the work and the author, who was variously described as foolish, heartless, blasphemous, and any combination of the three.

The uproar inspired Malthus to thoroughly revise his work for the second edition, published in 1803. The two margins on which he expanded the Essay were (1) laying out his arguments more clearly and in more explicit detail and (2) including vast amounts of empirical information in support of his theory of population. His pursuit of data took him on trips through Germany, Russia, and Scandinavia, making him one of the first economists to perform extensive field-work to gather cross-country data. Other than the inclusion of additional arguments and information that he gradually accumulated, the sixth edition, published in 1826, is largely the same as the second edition. (Except where noted, all of the passages quoted below from the Essay come from the sixth edition.)

Malthus most likely believed that the revisions he made would dispel a large amount of the heat he received after his book's initial publication. He was wrong. If anything, attacks against him increased in number and rancor. One detractor, whose criticism of Malthus will be examined below, went so far as to write that "I willingly plead guilty to the charge of regarding his doctrines with inexpressible abhorrence," and "Mr. Malthus' [creed] is not the religion of the Bible. On the contrary it is in diametrical opposition to it."1

Although attackers with that much venom do not appear anymore, the fundamental lack of understanding of Malthus' work continues to this day, to the point that what is "popularly known" about Malthus is the false picture, not the true one found in the Essay. Recently, a nationally syndicated columnist referred to "the 18th century economist Thomas Malthus, who claimed the world would starve because food production could never keep up with human population growth,"2 showing how inaccurate characterizations of Malthus' ideas from almost two hundred years ago have persisted to this day.

What Malthus Actually Wrote

The Concise Encyclopedia of Economics contains an entry on Population that describes the concerns classical and present-day economists have had over population growth, and how those concerns changed over time.

Malthus' main concerns were the determinants of population growth, the relationship between population and production, and how the bases of that relationship were the rational choices of foresighted individuals. The main tenets of his theory were laid out in Chapter 1, Book 1 of Essay. His starting point was the axiomatic notion that "population is necessarily limited by the means of subsistence," meaning that there cannot be more people walking around than everyone's total production, particularly food production, can support.

From there, he described the potential rates of growth for both population and production. Starting with population, he stated in the absence of any impediments, or checks, to population growth, the size of a given population would rise at an ever-increasing rate. To see how this works, imagine a population of 1,000 people whose birth and death rates are such that the population doubles in size with each successive generation. As the generations go by, that population would expand increasingly quickly, from 1,000 to 2,000 to 4,000 to 8,000 and so on.

In paragraph 9, Malthus wrote that "in no state that we have yet known, has the power of population been left to exert itself with perfect freedom," and so he could not determine how quickly a population with no checks on its advance would grow. As a matter of convenience, he still wanted some sort of benchmark to use in his analysis. For this, he looked toward the fledgling United States, where he believed the checks to population growth were lower than anywhere else and so population growth was highest. In paragraph 11, he notes that according to reports available at the time, "the population [in the northern states of America] has been found to double itself, for above a century and a half successively, in less than twenty-five years." Because a doubling every twenty-five years was the fastest actual population growth about which Malthus knew, he adopted it as a lower-bound estimate of population growth in the absence of any checks, writing in paragraph 16 that "It may safely be pronounced, therefore, that population, when unchecked, goes on doubling itself every twenty-five years, or increases in a geometrical ratio."

Readers familiar with the increases in food production and in overall production over the last few centuries are no doubt chafing at Malthus' assertion that food production can increase no faster than arithmetically. Such readers are asked to be patient, as this subject will be addressed in an upcoming column.

Turning to the potential rate of growth of production of the means of subsistence, specifically food, Malthus this time sought an upper-bound estimate so he could compare the most liberal estimate of food production growth with the most conservative estimate of population growth. He laid out his assumptions about food production growth in paragraphs 21, 24, and 25:

If it be allowed that by the best possible policy, and great encouragements to agriculture, the average produce of [Britain] could be doubled in the first twenty five years, it will be allowing, probably, a greater increase than could with reason be expected.

If this supposition be applied to the whole earth, and if it be allowed that the subsistence for man which the earth affords might be increased every twenty-five years by a quantity equal to what it at present produces, this will be supposing a rate of increase much greater than we can imagine that any possible exertions of mankind could make it.

It may be fairly pronounced, therefore, that, considering the present average state of the earth, the means of subsistence, under circumstances the most favourable to human industry, could not possibly be made to increase faster than in an arithmetical ratio.

Taking these two ratios together, then, and arbitrarily setting the initial level of both population and production at one, then according to paragraph 27, "the human species would increase as the numbers, 1, 2, 4, 8, 16, 32, 64, 128, 256, and subsistence as 1, 2, 3, 4, 5, 6, 7, 8, 9. In two centuries the population would be to the means of subsistence as 256 to 9; in three centuries as 4096 to 13, and in two thousand years the difference would be almost incalculable."

These geometric and arithmetic ratios are what most people who have heard of Malthus know about his work. Had Malthus stopped here, then it would be hard to dispute the popular misconception about his work—the numbers show population growing so much faster than production that starvation on a massive scale seems to be the inevitable conclusion.

But Malthus did not stop there. Recall that the geometric ratio pertained to population growth in the absence of any checks. It is a discussion of the possible checks, in theory and in practice, that comprises the bulk of Malthus' Essay. He discusses two types of checks, positive and preventive.

Positive checks are defined in Book I, Chapter 2, paragraph 9 as including "every cause, whether arising from vice or misery, which in any degree contributes to shorten the natural duration of human life." He listed several examples: "Under this head, therefore, may be enumerated all unwholesome occupations, severe labour and exposure to the seasons, extreme poverty, bad nursing of children, great towns, excesses of all kinds, the whole train of common diseases and epidemics, wars, plague, and famine." Positive checks of one sort or another work against the growth of all living things, plants and animals alike.

Preventive checks, on the other hand, are unique to humans because only humans possess the self-awareness, reason and foresight to look down the road and consciously decide whether or not to procreate. A person, as Malthus wrote in Book I, Chapter 2, paragraph 4,

cannot contemplate his present possessions or earnings, which he now nearly consumes himself... without feeling a doubt whether, if he follow the bent of his inclinations, he may be able to support the offspring which he will probably bring into the world.... Will he not lower his rank in life, and be obliged to give up in great measure his former habits? Will he not be unable to transmit to his children the same advantages of education and improvement that he had himself possessed? Does he even feel secure that, should he have a large family, his utmost exertions can save them from rags and squalid poverty, and their consequent degradation in the community?

"These considerations," he continues in the next paragraph, "are calculated to prevent, and certainly do prevent, a great number of persons in all civilized nations from pursuing the dictate of nature in an early attachment to one woman."

Malthus' study of preventive checks, which covered regions around the globe and in various stages in mankind's history, was a study of human agents making conscious, rational decisions calculated to maximize their own self-interest and the interest of their potential offspring. It was the examination of how individuals check their own behavior for their own benefit that elevated Malthus' Essay beyond a simple mathematical description of population growth, and into a work of economic theory and practice that was remarkably innovative for its day and well-respected by contemporary economists like Adam Smith and David Ricardo. However, this aspect of the Essay was ignored, misunderstood, or derided in much of the rest of society.

It is the interplay of both positive and preventive checks that, according to Malthus, keep human population from actually growing at a geometric rate. Although at some times and places when the means of subsistence suddenly expands greatly, as was the case when North American settlers were spreading across a continent of largely uncultivated land, populations could grow unimpeded by significant checks, eventually that growth would be met by a limitation on the amount of food that the land could produce. The impending food scarcity would, without a preventive check, generate positive checks in the form of food shortages, hunger, and poverty. However, thanks to mankind's cognitive abilities, people would see these dire consequences and, before they arose, impose on themselves a preventive check in the form of having fewer children. In this way, population would usually hover close to, but not go beyond, the means of subsistence.

This is not to say that famines, when the amount of food available in a certain location is simply not enough for everyone there to survive, could not occur. He was not blind to the fact that famines were a recurrent fact of life in his day. He wrote in Book II, Chapter 13, paragraph 18, that "though the principle of population cannot absolutely produce a famine, it prepares the way for one; and by frequently obliging the lower classes of people to subsist nearly on the smallest quantity of food that will support life, turns even a slight deficiency from the failure of the seasons into a severe dearth." According to Malthus, famines happen, and population pressures are a key factor in them. However, nothing in his theory of population growth necessitates the massive, widespread famine that many past and current writers claim was his main prediction.

Early Misconceptions about Malthus' Theory

Soon after Malthus' Essay was first published, many responses appeared to attack his work. One of the most vociferous critics was William Godwin, the English philosopher and writer whose discourse on population in his book, On Population (1793), first prompted Malthus to write his Essay. In 1820, Godwin published Of Population, subtitled Being an Answer to Mr. Malthus's Essay on That Subject, which was the source of the earlier quotes about "inexpressible abhorrence" and Malthus' creed being diametrically opposed to the Bible. In his On Population, Godwin founded his objections to Malthus' theory on two connected points.

First, Godwin claimed that Malthus' position was that people everywhere do in fact have enough babies such that if they all survived to adulthood, population would double in size every twenty-five years. Godwin then estimated how many births per marriage would be necessary for this doubling to occur, taking into account the number of babies that do not survive and the number of people who never marry. On page 29 of his On Population, he concluded that "When Mr. Malthus therefore requires us to believe in the geometrical ratio, or that the human species has a natural tendency to double itself every twenty-five years, he does nothing less in other words, than require us to believe that every marriage among human creatures produces on average... eight children." He then chastised Malthus for not examining the registers of marriages and births of different countries and realizing that so many children are not really born.

The French economist Frederic Bastiat defended Malthus from Godwin and other critics in Chapter 16 of Economic Harmonies (1996, first pub. 1850). On this question of the geometric ratio, Bastiat wrote in paragraph 52 that "Malthus never advanced the fatuous premise that 'mankind, in actual fact, multiplies in geometrical ratio.' He says, on the contrary, that this is not in fact the case, since he is investigating the obstacles that prevent it from being so, and he offers this ratio merely as a formula to show the physiological potential of reproduction." That Godwin and others did not see this, particularly after Malthus' clarifications in the second edition, betrays at least a case of willful blindness.

Godwin's second point began with his noting that in most European countries, population was more or less stable. He then claimed that Malthus' theory could not be true unless huge numbers of all of those children being born in the light of Godwin's first assertion were dying before they reached maturity, a fact not borne out by birth and death registers. Further, Godwin states that Malthus himself argues implicitly that population is not checked by fewer children being born, but by early deaths. On page 32, Godwin wrote that:

Mr. Malthus has added in his subsequent editions, to the two checks upon population, viz. vice and misery, as they stood in the first, a third which he calls moral restraint. But then he expressly qualifies this by saying, "the principle of moral restraint has undoubtedly in past ages operated with very inconsiderable force;" subjoining at the same time his protest against "any opinion respecting the probable improvement of society, in which we are not borne out by the experience of the past."

It is clearly therefore Mr. Malthus's doctrine, that population is kept down in the Old World, not by a smaller number of children being born among us, but by the excessive number of children that perish in their nonage through the instrumentality of vice and misery.

According to Godwin's indictment of Malthus, then, Malthus believed that moral restraint, or to use the terminology introduced in a previous section, the use of preventive checks, was insignificant in past ages. Further, Godwin maintained that Malthus believed that experience provides no reason to believe that society has improved in this regard since that time. Therefore, Godwin claimed, Malthus must not believe that moral restraint, or preventive checks, were of any significance during the men's own time.

Let's take a closer look at Godwin's argument, and see where it goes wrong. First, with his phrase "subjoining at the same time," Godwin gives the impression that the two quotes from Malthus are connected. However, an examination of Godwin's footnotes reveals that these quotes appear nearly four hundred pages apart, the first quote being on page 384 of the second edition of Essay, while the second quote is found in paragraph 8 of the Preface to the second edition.3 Therefore, Malthus can hardly be thought to have intended the two quotes to be part of a continuous argument.

Godwin did something even sneakier. Godwin claimed that Malthus protested against "any opinion respecting the probable improvement of society, in which we are not borne out by the experience of the past," (my italics). If we check this against what Malthus actually wrote, we find that Godwin cropped a phrase out of the Preface and subtly altered the words, creating a crucial difference in meaning. A fuller and more accurate quote from Malthus is "I hope that I have not violated the principles of just reasoning; nor expressed any opinion respecting the probable improvement of society, in which I am not borne out by the experience of the past," (again, my italics). Malthus was not protesting against the idea that society may have improved, as Godwin portrayed by changing Malthus' use of the first person to the third person. Instead, Malthus was claiming that any assertion he actually did make about society's improvement was based on the experience of the past. Malthus did not deny that society had improved in terms of moral restraint, he believed that it did and that the evidence confirmed it!

On Malthus' part, the "past ages" to which he referred in the second edition of Essay could be interpreted as meaning any time from the centuries immediately prior to his writing to the furthest reaches of human history. This phrase, taken alone, leaves open ambiguity about whether Malthus thought that moral restraint, or the preventive check, was active in his day. Unfortunately for Godwin, Malthus made unambiguous remarks about his belief in the presence of a preventive check working to cause fewer births. In paragraph 9 of Chapter 4 of the first edition, he wrote that "The preventive check appears to operate in some degree through all the ranks of society in England." In the first paragraph of Book II, Chapter 8 of the sixth edition, Malthus is even more forceful: "The most cursory view of society in this country must convince us, that throughout all ranks the preventive check to population prevails in a considerable degree." It strains credulity that one could read with good faith even Malthus' earliest edition and not recognize that he thought a preventive check was at work.

Improvement in the Human Condition

A final subject in which Malthus' views have been misunderstood is his thoughts concerning whether poverty could be reduced and the human condition, especially of the poor, might be improved. He is characterized as having been utterly pessimistic on this front, believing that a gloomy, miserable existence was all that is in store for us.

Godwin wrote dramatically on this theme. On pages 111-112 of On Population, he wrote that "The great tendency and effect of Mr. Malthus's book were to warn us against making mankind happy. Such an event must necessarily lead, according to him, to the most pernicious consequences. A due portion of vice and misery was held out to us as the indispensible preservative of society." More disheartening, on page 144 he described Malthus as "fully convinced that he has shewn in 'the laws of nature and the passions of mankind' an evil, for which all remedies are feeble, and before which courage must sink into despair."

Even Bastiat, who as we have seen defended Malthus on other fronts, believed that the end result of Malthus' thinking was perpetual poverty. In Chapter 16, paragraph 90 of Economic Harmonies, he opined that "Malthus... was consequently led to pessimistic conclusions, and these in turn have aroused public opinion against him.... Hence, it was his belief that the repressive (or, as he called it, the positive) check would be the decisive one; in other words, vice, poverty, war, crime, etc." Bastiat continued this thought in paragraph 98:

He declares that, taking into consideration absolute fertility, on the one hand, and, on the other, the means of limiting it in the form of either repression or prevention, we find that the result is nonetheless a tendency for population to increase faster than the means of subsistence.... If it were true, as Malthus says, that for each increase in the means of existence there is a corresponding and greater increase in population, the poverty of our race would necessarily be constantly on the increase, and civilization would stand at the beginning of time, and barbarism at the end.

Malthus did persistently discuss how population grows until it is limited by the means of subsistence, and from that, critics and supporters alike came away from his Essay with the impression that Malthus saw no betterment in humanity's future. However, there are several instances in which Malthus blatantly and unmistakably expressed hope for improvement, albeit perhaps slow, in the condition of the poor and humanity in general.

We are not however to relax our efforts in increasing the quantity of provisions, but to combine another effort with it; that of keeping the population, when once it has been overtaken, at such a distance behind, as to effect the relative proportion which we desire; and thus unite the two grind [sic] desiderata, a great actual population, and a state of society, in which abject poverty and dependence are comparatively but little known; two objects which are far from being incompatible.

More concretely, in paragraph 2 of Book IV, Chapter 4, he predicted that "I can easily conceive that this country, with a proper direction of the national industry, might, in the course of some centuries, contain two or three times its present population, and yet every man in the kingdom be much better fed and clothed than he is at present."

Finally, paragraph 14 of Book IV, Chapter 14, Malthus' concluding paragraph, should have dispelled any notion that he saw no progress in store for humanity:

On the whole, therefore, though our future prospects respecting the mitigation of the evils arising from the principle of population may not be so bright as we could wish, yet they are far from being entirely disheartening, and by no means preclude that gradual and progressive improvement in human satiety, which, before the late wild speculations on this subject, was the object of rational expectation.... We have every reason to believe that it will always consist of a class of proprietors and a class of labourers; but the condition of each, and the proportion which they bear to each other, may be so altered, as greatly to improve the harmony and beauty of the whole.

Conclusion

We have seen that since the publication of his Essay and continuing today, Malthus has been misrepresented and, at times, mistreated in the ways that others have described his work, which was not nearly as dire and pessimistic as many people have believed. In the next Teacher's Corner, we will explore how a similar experience has greeted those in this century who have written unexpected and unwelcome things about humanity's usage of natural resources and relationship with the environment. We will also address aspects of Malthus' theory which have proved to be wrong.

The first quote provided here by Godwin does not appear in the text of either the first or sixth edition, the two editions available on Econlib. The Preface to the second edition, which contains the second quote Godwin provided, was reprinted in Malthus' sixth edition, and so is available.

*Morgan Rose is a Ph.D. candidate in economics at Washington University in St. Louis, with research interests in industrial organization, corporate governance and economic history.